1. Field of the Invention
This invention relates to an activating device for occupant protection device and the method for controlling the activating device. In more detail, the present invention relates to an activating device for an occupant protection device and a controlling method therefor by early stage and accurate activation by providing a front sensor provided in the vehicle front most portion for detecting a vehicle collision at an early stage and a floor sensor provided at the central portion of the vehicle.
2. Description of the Related Art
An occupant protection device such as an air bag installed in a vehicle adjusts the activating timing of the occupant protection device based on the time change of the vehicle deceleration detected by a deceleration sensor provided in the vehicle. In order to activate with a more proper timing, it is important for the occupant protection device to detect the vehicle collision without fail. The applicant of this invention has proposed one of such collision-detecting device that includes an activating device for the occupant protection device that includes a floor sensor provided at the center of the vehicle body and a front sensor arranged at the front of the vehicle to detect the vehicle deceleration. Based on the detected deceleration, the activating timing of the occupant protection device is controlled. (Japanese patent Laid-Open publication H10-152014). According to this activating device, the occupant protection device can be timely activated even under a vehicle collision, the impact of which could not be detected by a floor sensor only.
By the way, when the vehicle is under collision condition, an early stage the vehicle collision condition is detected by the front sensor. By arranging the front sensor at the vehicle front most portion where the impact of the collision is easily detected, the front sensor can detect the vehicle collision more sensibly and by using the detected value, the protecting device can be activated early and accurately.
Further, it is preferable for the activating device of the occupant protection device to be structured so that the front sensor arranged at the vehicle portion where the impact can be easily detected, can function without fail.